The present invention relates to the burn-in of high power semiconductor devices and, in particular, to an apparatus that is capable of controlling the temperature of high power semiconductor devices during burn-in.
The continuing miniaturization of electronic circuit components has resulted in the creation of semiconductor devices having extremely high power densities. During the burn-in of such devices, power dissipation is a major concern as the devices often generate a great deal of heat. A further concern regarding the burn-in of high power semiconductor devices is that individual devices in a single lot often have power dissipations which vary by a substantial amount. The amount of cooling each individual device needs during burn-in will therefore vary.
One way in which semiconductor devices have been cooled during burn-in is through the continual circulation of air through the burn-in chamber. While this method may be adequate for the burn-in of ordinary semiconductor devices, it is not adequate for dissipating the heat generated by high power semiconductor devices during burn-in.
Another way in which semiconductor devices have been cooled during burn-in is through direct immersion in a dielectric liquid. While more effective in cooling high power-semiconductor devices than forced air circulation, direct immersion presents many practical problems such as the difficult task of lowering the burn-in board into the liquid.
In addition to their many problems, none of the above described methods for cooling semiconductor devices during burn-in is capable of sensing the temperature of each individual semiconductor device and providing a corresponding degree of cooling for that device.